Assembly and method for shifting between modes of operation for a washing machine appliance

Abstract

A washing machine appliance and a method of operation thereof are provided for shifting between different modes such as wash, rinse, and/or spin modes. A clutch is used to shift between the different modes of operation. Alignment of the clutch, particularly the clutch teeth, is provided so as to allow for proper engagement of the clutch and motor or to properly align the clutch teeth for disengagement and locking with locking teeth carried upon e.g., a platform lock.

What is claimed is: 
     
       1. A method for operating a washing machine appliance, the appliance including locking teeth having a fixed position, a motor comprising a stator with a plurality of coils, a rotor with a plurality of magnets and a plurality of rotor teeth, a clutch having opposing sides along the axial direction and that includes a first plurality of clutch teeth along one of the opposing sides and a second plurality of clutch teeth along the other opposing side, the clutch also being-slidable along an axis of rotation defined by the rotor, the method comprising:
 energizing at least one coil of the plurality of coils of the stator so as to rotate the rotor to a position where the at least one coil is aligned with at least one magnet of the plurality of magnets carried by the rotor; 
 holding the rotor at a position where the at least one coil is aligned with at least one magnet of the plurality of magnets carried by the rotor while the at least one coil is energized; 
 aligning a plurality of rotor teeth on the rotor with the first plurality of clutch teeth by the energizing and the holding; 
 sliding the clutch along the axis of rotation of the motor so as to engage the first of plurality of clutch teeth with the plurality of rotor teeth; 
 re-energizing one or more of the plurality of coils of the stator while the first plurality of clutch teeth are engaged with the plurality of rotor teeth; 
 positioning the rotor during the re-energizing so as to align the second plurality of clutch teeth with the locking teeth; 
 holding the rotor during the re-energizing and after the positioning so as to maintain alignment of the second plurality of clutch teeth with the locking teeth while the first plurality of clutch teeth are engaged with the plurality of rotor teeth; and 
 sliding the clutch along the axis of rotation so as to engage the second plurality of clutch teeth with the locking teeth. 
 
     
     
       2. The method for operating a washing machine appliance as in  claim 1 , further comprising jogging the motor so as to release the first plurality of clutch teeth from the plurality of rotor teeth. 
     
     
       3. The method for operating a washing machine appliance as in  claim 2 , further comprising jogging the motor so as to release the second plurality of clutch teeth from the plurality of locking teeth of the appliance. 
     
     
       4. The method for operating a washing machine appliance as in  claim 1 ,
 wherein the plurality of magnets of the rotor comprises X magnets that are circumferentially spaced about the axis of rotation of the motor wherein X is an integer and X is ≧2; and 
 wherein the first plurality of clutch teeth comprises Y teeth with Y=(X/2)* n, where n is any positive integer. 
 
     
     
       5. The method for operating a washing machine appliance as in  claim 1 ,
 wherein the plurality of magnets of the rotor comprises thirty-six magnets that are circumferentially spaced about the axis of rotation of the rotor with the polarity arranged in an alternating manner; and 
 wherein the first plurality of clutch teeth comprises thirty-six teeth and the plurality of rotor teeth comprises thirty-six teeth. 
 
     
     
       6. A method for operating a washing machine appliance, the appliance including locking teeth having a fixed position, a motor comprising a stator with a plurality of coils, a rotor with a plurality of magnets and a plurality of rotor teeth, a clutch having opposing sides along the axial direction and that includes a first plurality of clutch teeth along one of the opposing sides and a second plurality of clutch teeth along the other opposing side, the clutch also being-slidable along an axis of rotation defined by the rotor, the method comprising:
 energizing one or more of the plurality of coils of the stator while the first plurality of clutch teeth are engaged with the plurality of rotor teeth; 
 positioning the rotor during the energizing so as to align the second plurality of clutch teeth with the locking teeth; 
 holding the rotor during the energizing and after the positioning so as to maintain alignment of the second plurality of clutch teeth with the locking teeth while the first plurality of clutch teeth are engaged with the plurality of rotor teeth; and 
 sliding the clutch along the axis of rotation so as to engage the second plurality of clutch teeth with the locking teeth. 
 
     
     
       7. The method for operating a washing machine appliance as in  claim 6 , further comprising jogging the motor so as to release the first plurality of clutch teeth from the rotor teeth. 
     
     
       8. The method for operating a washing machine appliance as in  claim 7 , wherein the energizing comprises energizing at least one coil of the stator so as to rotate and hold the rotor at a position where the coil is aligned with at least one magnet carried by the rotor. 
     
     
       9. The method for operating a washing machine appliance as in  claim 6 , further comprising:
 jogging the motor so as to release the first plurality of clutch teeth from the plurality of rotor teeth; and 
 sliding the clutch along the axis of rotation so as to disengage the clutch from the rotor. 
 
     
     
       10. The method for operating a washing machine appliance as in  claim 9 , further comprising:
 re-energizing at least one coil of the stator so as to rotate and hold the rotor at a position where the coil is aligned with at least one magnet carried by the rotor; 
 positioning the rotor during the re-energizing so as to align the first plurality of clutch teeth with the plurality of rotor teeth while the second plurality of clutch teeth are engaged with the locking teeth; 
 holding the rotor during the re-energizing and after the positioning so as to maintain alignment of the first plurality of clutch teeth with the plurality of rotor teeth while the second plurality of clutch teeth are engaged with the locking teeth; and 
 sliding the clutch along the axis of rotation so as to engage the first plurality of clutch teeth with the plurality of rotor teeth. 
 
     
     
       11. The method for operating a washing machine appliance as in  claim 6 , wherein the plurality of magnets of the rotor comprises X magnets that are circumferentially spaced about the axis of rotation; wherein X is an integer and X is ≧2; and wherein the first plurality of clutch teeth comprises Y teeth with Y=(X/2)* n, where n is any positive integer. 
     
     
       12. The method for operating a washing machine appliance as in  claim 6 , wherein the plurality of magnets of the rotor comprises thirty-six magnets that are circumferentially spaced about the axis of rotation with the polarity arranged in an alternating manner; and wherein the first plurality of clutch teeth comprises thirty-six teeth and the plurality of rotor teeth comprises thirty-six teeth.